Most "gym website" requests that come in as dev work aren't really about design — they're about wiring three systems together correctly: the page layer (WordPress), the scheduling layer (a booking plugin or third-party tool like Mindbody/Glofox), and the payment layer (Stripe/PayPal recurring subscriptions).
The architecture decision that matters most early: do you build booking natively into WooCommerce (using a bookings/appointments plugin), or do you integrate an external SaaS scheduler via API/embed? Native WooCommerce booking keeps everything in one database and avoids a second monthly subscription fee for the client, but it requires more setup time upfront — configuring product-as-class-slot logic, capacity limits, and syncing recurring membership products to unlock discounted per-class pricing. External tools like Mindbody are faster to bolt on but introduce a second source of truth for schedule data and usually cost the client a recurring per-member fee on top of hosting.
For recurring membership billing, Stripe's Billing/Subscriptions API (or WooCommerce Subscriptions if staying in the WP ecosystem) handles proration, plan changes, and failed-payment retry logic — which matters a lot for gyms since a chunk of monthly churn is just expired cards, not people actually canceling.
On a recent build for a two-trainer personal training studio, we went fully native WooCommerce: custom booking product type, Stripe Subscriptions for three membership tiers, and a lightweight trainer-availability calendar built without a third-party plugin dependency. Total delivery: just over two weeks.
Full non-technical cost breakdown for anyone budgeting this kind of project: https://amanurrahman.com/blog-post/gym-fitness-studio-website-cost